<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8" />
		<title>viewport适配</title>
		<meta name="viewport" content="width=375"/>
		<style>
			*{
				margin: 0;
				padding: 0;
			}
			#demo{
				width: 345px;
				height: 150px;
				background-color: skyblue;
				margin:0 auto;
				margin-top: 15px;
				border: 1px solid black;
			}
		</style>
	</head>
	<body>
		<div id="demo"></div>
	</body>
</html>